| Primary satellite | Secondary satellite |
| Name | ARGOS | COSMOS 2251 DEB |
| Spacetrack catalog number | 25634 | 47052 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Apr 14 12:58 | 2021 Apr 13 13:44 |
| Time of closest approach (UTC) | 2021 Feb 28 16:26:18.243 |
| Minimum distance | 5.400 km |
| Height difference | 4.112 km |
| Relative speed | 14.595 km/s |
| Angle between velocity vectors | 159° |
| Geographic position | 65.6°S, 151.6°W |
| Height | 844 km |
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